Battle against the clock to prevent millions of humpback salmon in Norwegian rivers – news Troms and Finnmark

The unwanted humpback salmon comes from Russia and invaded Finnmark’s rivers by the tens of thousands last year. The species comes every other year, so this has been a quiet summer. But next summer it can really hit. – We have a formidable task ahead of us to be prepared for next year. There is no doubt that we work under strong time pressure, says Eirik Frøiland. He is a fisheries manager and heads the Norwegian Environment Agency’s national competence group for humpback salmon. The national action plan against humpback salmon states that the rivers in the farthest east of Finnmark, from the border to Tana, will have traps in the first instance. Photo: Knut-Sverre Horn / news Initially, efforts will be concentrated on Eastern Finnmark, where the problem has been greatest. This week, Frøiland was able to show off a new salmon trap that has been set up in Vestre Jakobselv in Vadsø. – There are a handful of rivers that have been tested now. We have set ourselves a milestone of covering at least the pupils between Grense Jakobselv and Tana. Then we’ll see how far the budgets go. We see that the needs are also present further west, says Frøiland. Facts about humpback salmon Humpback salmon (often called Russel salmon) naturally belong in northern parts of the Pacific Ocean. The average weight is about 2 kg for mature salmon. The mature male gets a hump on the front of his back. Both the female and the male have a white underside, grey-green sides and fairly large spots on the back, sides and tail. In the 1960s, humpback salmon began to spread to northern Norwegian rivers after it had been released on the Kola Peninsula in Russia. 20,029 humpback salmon were registered caught in Norway in 2019, compared to 6,594 in 2017. Humpback salmon have a two-year life cycle, and both males and females die after spawning. In Troms and Finnmark, the humpback salmon is most numerous, but it has also been recorded in rivers as far south as the Oslofjord. Source: Nina and the Species Data Bank Missing traps for large rivers There is a reason why the first phase does not include the mighty – and very important – Tana River: No one has found a suitable solution. – The bigger the river, the bigger the challenge. The trap we have here in Vestre Jakobselv has its limitations. According to the advice we have received, it will not work in a river as large as the Tana, says Frøiland. Eirik Frøiland hopes that it will become clear during the autumn how to prevent humpback salmon also in the largest rivers. Photo: news A separate group has been tasked with finding traps that work for the largest rivers, such as the Tanaelva and Altaelva, perhaps also the Reisaelva and Målselva. Their report is due in the autumn. So far, Frøiland is optimistic. – I think it will be possible to find solutions also for rivers as large as the Tana. We know that there are catchment facilities in larger rivers in, for example, Russia. State administrator Elisabeth Vik Aspaker in Troms and Finnmark believes they are “reasonably well off” in the job of testing salmon traps. – But it is a race against the clock, because we see that the amount of humpback salmon is increasing violently. That is why it is important, the job that must now be done. Artificial intelligence The traps that are now set out are based on all the fish being caught – and humpback salmon being sorted out manually. In Berlevåg, the local fishermen’s association has received help from Huawei to distinguish humpback salmon automatically using cameras and artificial intelligence. Frøiland believes that this technology is not quite up to scratch yet, but hopes that it can be useful. Requires people in shifts Until then, a formidable job awaits the local river contractors. Members and volunteer tourists took on the humpback salmon in Vestre Jakobselv as a volunteer last year. Not another year will pass, states May-Britt Dervo, deputy leader of the Vestre Jakobselv hunting and fishing association. Last time, at least 10,000 humpback salmon came into her river. Next year it could be well over ten times as much. – We don’t know if there will be 30,000 humpback salmon or 150,000, but we have to have a plan, says May-Britt Dervo of the Vestre Jakobselv hunting and fishing association. She hopes to sell the humpback salmon – and thereby finance the staffing of the salmon trap. Photo: news – With the estimate that has been made, it will not be possible to carry out the rearing of fella on a voluntary basis. Suddenly we are standing here with 15,000 humpback salmon, says Dervo. – We have to hire people who work in shifts, and we have to get a good infrastructure on land that means we can get rid of the fish continuously. Dervo believes the state must pay, and state administrator Aspaker is on the slide. – We know that last year people used their holidays and almost all their free time. It cannot continue like this. If we are going to set up traps, we also have to find money to smoke the traps, Aspaker tells news. Work for weeks was the only option when 10,000 humpback salmon flowed into Vestre Jakobselv last year. Next year, people must be hired, the local fishermen’s association believes. Photo: Hanne Wilhelms / news Do not eradicate, but limit Humpback salmon are much less faithful to their childhood river than Atlantic salmon are. Therefore, it will come to Norway as long as there are large stocks in Russia. – We do not have a goal to eradicate the humpback salmon, but to limit it to such an extent that it does not have significant consequences for the ecology and water quality of the Norwegian rivers, says Frøiland. The battle that is now taking place in Eastern Finnmark may have significance far beyond Norway’s borders. – In large rivers such as the Tana, there could be millions of humpback salmon if they are released completely freely. It will then spread further in Norway and potentially many countries in Europe, says Frøiland. – We have a responsibility to try to prevent that from happening, so that Norway does not become a bridgehead for further invasion in other countries. 1,090 humpback salmon were caught in an hour and a half last year, but no one could ensure that it was taken care of as food. Photo: Hanne Wilhelms / news Can become a resource Last summer, the vast majority of humpback salmon were dumped. Some went to dog food, and very little to human food. The aim is to make better use of the resource. – We hear about local fish buyers here in Finnmark who are interested. Now it is a matter of finding ways to take care of the salmon that is taken out of the trap in order to preserve its quality, so that it can become a food resource. There are certainly opportunities here, says Elisabeth Vik Aspaker. The quality of the meat deteriorates shortly after the fish enters the river. But the female salmon are still a resource: the roe is good raw material for caviar. The salmon trap must be taken down before the ice settles, but a system of rails on the bottom should make it possible to put it back up in a day. Photo: news



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